Implement GetTextFromRange(), GetTextRange() and GetSelectionRange() for ArcImeService.

components/arc/ime/arc_ime_service.cc

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "components/arc/ime/arc_ime_service.h"
 
 #include <utility>
 
 #include "base/logging.h"
 #include "base/strings/utf_string_conversions.h"
 #include "components/arc/ime/arc_ime_bridge_impl.h"
 #include "components/exo/shell_surface.h"
 #include "components/exo/surface.h"
 #include "ui/aura/env.h"
 #include "ui/aura/window.h"
 #include "ui/aura/window_tree_host.h"
 #include "ui/base/ime/input_method.h"
 #include "ui/events/base_event_utils.h"
 #include "ui/events/event.h"
 #include "ui/events/keycodes/keyboard_codes.h"
+#include "ui/gfx/range/range.h"
 
 namespace arc {
 
 namespace {
 
 class ArcWindowDelegateImpl : public ArcImeService::ArcWindowDelegate {
  public:
   explicit ArcWindowDelegateImpl(ArcImeService* ime_service)
     : ime_service_(ime_service) {}
 
@@ skipping 193 matching lines @@
     input_method->CancelComposition(this);
 }
 
 void ArcImeService::ShowImeIfNeeded() {
   ui::InputMethod* const input_method = GetInputMethod();
   if (input_method && input_method->GetTextInputClient() == this) {
     input_method->ShowImeIfNeeded();
   }
 }
 
+void ArcImeService::OnCursorRectChangedWithSurroundingText(
+    const gfx::Rect& rect,
+    const gfx::Range& text_range,
+    const base::string16& text_in_range,
+    const gfx::Range& selection_range) {
+  text_range_ = text_range;

[hidehiko, 2017/05/11 14:32:32]

These values should be invalidated when the text is being updated? E.g. updating
composing text / focus switching etc.?

[yhanada, 2017/05/12 07:52:06]

These value should be used from InputMethod::OnCaretBoundsChanged(). I changed
to invalidate them after OnCaretBoundsChanged() call.

+  text_in_range_ = text_in_range;
+  selection_range_ = selection_range;
+  OnCursorRectChanged(rect);
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 // Overridden from keyboard::KeyboardControllerObserver
 void ArcImeService::OnKeyboardBoundsChanging(const gfx::Rect& new_bounds) {
   if (!focused_arc_window_)
     return;
   aura::Window* window = focused_arc_window_;
   // Multiply by the scale factor. To convert from DPI to physical pixels.
   gfx::Rect bounds_in_px = gfx::ScaleToEnclosingRect(
       new_bounds, window->layer()->device_scale_factor());
   ime_bridge_->SendOnKeyboardBoundsChanging(bounds_in_px);
@@ skipping 86 matching lines @@
 
   // Add the offset of the window showing the ARC app.
   // TODO(yoshiki): Support for non-arc toplevel window. The following code do
   // not work correctly with arc windows inside non-arc toplevel window (eg.
   // notification).
   converted.Offset(
       window->GetToplevelWindow()->GetBoundsInScreen().OffsetFromOrigin());
   return converted;
 }
 
+bool ArcImeService::GetTextRange(gfx::Range* range) const {
+  if (!text_range_.IsValid())
+    return false;
+  *range = text_range_;
+  return true;
+}
+
+bool ArcImeService::GetSelectionRange(gfx::Range* range) const {
+  if (!selection_range_.IsValid())
+    return false;
+  *range = selection_range_;
+  return true;
+}
+
+bool ArcImeService::GetTextFromRange(const gfx::Range& range,
+                                     base::string16* text) const {
+  if (!text_range_.IsValid() || range != text_range_)

[hidehiko, 2017/05/11 14:32:31]

Could you document the limitation of the range?
(IIUC, technically it is possible to support sub-range of |text_range_|, but it
is not necessary for some reason?)

[yhanada, 2017/05/12 07:52:06]

As I commented above, I suppose that this method is called only from
InputMethod::OnCaretBoundsChanged(). In that method, the range obtained from
GetTextRange() is used as the argument of this method. It's why I added |range
!= text_range_|.

I added the comment.

+    return false;
+  *text = text_in_range_;
+  return true;
+}
+
 ui::TextInputMode ArcImeService::GetTextInputMode() const {
   return ui::TEXT_INPUT_MODE_DEFAULT;
 }
 
 base::i18n::TextDirection ArcImeService::GetTextDirection() const {
   return base::i18n::UNKNOWN_DIRECTION;
 }
 
 void ArcImeService::ExtendSelectionAndDelete(size_t before, size_t after) {
   ime_bridge_->SendExtendSelectionAndDelete(before, after);
 }
 
 int ArcImeService::GetTextInputFlags() const {
   return ui::TEXT_INPUT_FLAG_NONE;
 }
 
 bool ArcImeService::CanComposeInline() const {
   return true;
 }
 
 bool ArcImeService::GetCompositionCharacterBounds(
     uint32_t index, gfx::Rect* rect) const {
   return false;
 }
 
 bool ArcImeService::HasCompositionText() const {
   return has_composition_text_;
 }
 
-bool ArcImeService::GetTextRange(gfx::Range* range) const {
-  return false;
-}
-
 bool ArcImeService::GetCompositionTextRange(gfx::Range* range) const {
   return false;
 }
 
-bool ArcImeService::GetSelectionRange(gfx::Range* range) const {
-  return false;
-}
-
 bool ArcImeService::SetSelectionRange(const gfx::Range& range) {
   return false;
 }
 
 bool ArcImeService::DeleteRange(const gfx::Range& range) {
   return false;
 }
 
-bool ArcImeService::GetTextFromRange(
-    const gfx::Range& range, base::string16* text) const {
-  return false;
-}
-
 bool ArcImeService::ChangeTextDirectionAndLayoutAlignment(
     base::i18n::TextDirection direction) {
   return false;
 }
 
 bool ArcImeService::IsTextEditCommandEnabled(
     ui::TextEditCommand command) const {
   return false;
 }
 
 }  // namespace arc